Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash	$ 239,012	$ 153,299
Restricted cash	786	786
Prepaid expenses and other assets, current	48,262	42,899
Total current assets	288,060	196,984
Non-current assets:
Property and equipment, net	33,543	38,046
Right of use assets, net	21,199	51,637
Long-term deposits	1,836	2,625
Prepaid expenses and other assets, non-current	2,939	3,033
Deferred tax asset	2,034	1,754
Intangible assets, net	135	158
Total assets	349,746	294,237
Current liabilities:
Accounts payable	2,259	2,263
Accrued expenses and other liabilities	24,683	27,781
Lease liabilities	3,657	3,590
Total current liabilities	30,599	33,634
Non-current liabilities:
Lease liabilities	19,580	50,571
Total liabilities	50,179	84,205
Shareholders' equity:
Additional paid-in capital	716,544	595,016
Accumulated other comprehensive loss	(4,588)	(5,861)
Accumulated deficit	(412,510)	(379,244)
Total shareholders' equity	299,567	210,032
Total liabilities and shareholders' equity	349,746	294,237
Ordinary shares
Shareholders' equity:
Share value	3	3
Deferred shares
Shareholders' equity:
Share value	0	0
Deferred B Shares
Shareholders' equity:
Share value	118	118
Deferred C Shares
Shareholders' equity:
Share value	$ 0	$ 0

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).